<template>
  <!-- 商品分类导航 -->
  <div class="type-nav">
    <div class="container">
      <div @mouseleave="leaveIndex">
        <h2 class="all" @mouseover="enterShow">全部商品分类</h2>
        <div class="sort" v-show="show">
          <div class="all-sort-list2" @click="goSearch">
            <div
              class="item"
              v-for="(c1, index) in categoryList"
              :key="c1.categoryId"
              :class="{ cur: currentIndex == index }"
            >
              <h3 @mouseenter="changeIndex(index)">
                <a
                  :data-categoryName="c1.categoryName"
                  :data-category1Id="c1.categoryId"
                  @click="classification1(c1)"
                  >{{ c1.categoryName }}</a
                >
              </h3>
              <div
                class="item-list clearfix"
                :style="{ display: currentIndex == index ? 'block' : 'none' }"
              >
                <div
                  class="subitem"
                  v-for="c2 in c1.categoryChild"
                  :key="c2.categoryId"
                >
                  <dl class="fore">
                    <dt>
                      <a
                        :data-categoryName="c2.categoryName"
                        :data-category2Id="c2.categoryId"
                        @click="classification2(c2)"
                        >{{ c2.categoryName }}</a
                      >
                    </dt>
                    <dd>
                      <em
                        v-for="c3 in c2.categoryChild"
                        :key="c3.categoryId"
                      >
                        <a
                          :data-categoryName="c3.categoryName"
                          :data-category3Id="c3.categoryId"
                          @click="classification3(c3)"
                          >{{ c3.categoryName }}</a
                        >
                      </em>
                    </dd>
                  </dl>
                </div>
              </div>
            </div>
          </div>
        </div>
      </div>

      <nav class="nav">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav>
    </div>
  </div>
</template>

<script>
import { mapState } from "vuex";
import Debounce from "@/method/防抖函数";
export default {
  name: "TypeNav",
  data() {
    return {
      //当前这个属性决定了到底那个h3身上有类名
      currentIndex: -1,
      show: true,
    };
  },
  mounted() {
    console.log(this.$route);
    if (this.$route.name == "search" || this.$route.name == "detail") {
      //根据路由信息判断是否在搜索页面，如果是则默认隐藏三级分类
      this.show = false;
    }
  },
  computed: {
    ...mapState({
      categoryList: (state) => {
        return state.home.categoryList;
      },
    }),
  },
  methods: {
    //三级分类中的一级分类防抖
    changeIndex: Debounce(
      function (index) {
        this.currentIndex = index;
      },
      500,
      true
    ),
    //鼠标移出“全部分类”事件
    leaveIndex() {
      this.currentIndex = -1;
      if (this.$route.name == "search" || this.$route.name == "detail") {
        //根据路由信息判断是否在搜索页面，如果是且鼠标移入“全部分类”则展开分类
        this.show = false;
      }
    },
    //鼠标移入事件
    enterShow() {
      if (this.$route.name == "search" || this.$route.name == "detail") {
        //根据路由信息判断是否在搜索页面，如果是且鼠标移入“全部分类”则展开分类
        this.show = true;
      }
    },
    //点击分类中的类目跳转搜索页面
    goSearch(event) {
      //event.target:获取到的是出发事件的元素(div、h3、a、em、dt、dl)
      let node = event.target;
      //给a标签添加自定义属性data-categoryName,全部的字标签当中只有a标签带有自定义属性，别的标签名字----dataset纯属扯淡
      let { categoryname, category1id, category2id, category3id } =
        node.dataset;
      //第二个问题解决了：点击的到底是不是a标签（只要这个标签身上带有categoryname）一定是a标签
      //当前这个if语句：一定是a标签才会进入
      if (categoryname) {
        //准备路由跳转的参数对象
        let loction = { name: "search" };
        let query = { categoryName: categoryname };
        //一定是a标签：一级目录
        if (category1id) {
          query.category1Id = category1id;
          //一定是a标签：二级目录
        } else if (category2id) {
          query.category2Id = category2id;
          //一定是a标签：三级目录
        } else {
          query.category3Id = category3id;
        }
        //判断：如果路由跳转的时候，带有params参数，捎带脚传递过去
        if (this.$route.params) {
          loction.params = this.$route.params;
          //动态给location配置对象添加query属性
          loction.query = query;
          //路由跳转
          this.$router.push(loction);
        }
      }
    },
    classification1(c1) {
      console.log(c1);
      this.$emit("category", c1.categoryId, "category1Id",c1.categoryName);
    },
    classification2(c2) {
      this.$emit("category", c2.categoryId, "category2Id",c2.categoryName);
    },
    classification3(c3) {
      this.$emit("category", c3.categoryId, "category3Id",c3.categoryName);
    },
  },
};
</script>

<style scoped lang='less'>
.type-nav {
  border-bottom: 2px solid #e1251b;

  .container {
    width: 1200px;
    margin: 0 auto;
    display: flex;
    position: relative;

    .all {
      width: 210px;
      height: 45px;
      background-color: #e1251b;
      line-height: 45px;
      text-align: center;
      color: #fff;
      font-size: 14px;
      font-weight: bold;
    }

    .nav {
      a {
        height: 45px;
        margin: 0 22px;
        line-height: 45px;
        font-size: 16px;
        color: #333;
      }
    }

    .sort {
      position: absolute;
      left: 0;
      top: 45px;
      width: 210px;
      height: 461px;
      position: absolute;
      background: #fafafa;
      z-index: 999;

      .all-sort-list2 {
        .item {
          h3 {
            line-height: 30px;
            font-size: 14px;
            font-weight: 400;
            overflow: hidden;
            padding: 0 20px;
            margin: 0;

            a {
              color: #333;
            }
          }

          .item-list {
            display: none;
            position: absolute;
            width: 734px;
            min-height: 460px;
            background: #f7f7f7;
            left: 210px;
            border: 1px solid #ddd;
            top: 0;
            z-index: 9999 !important;

            .subitem {
              float: left;
              width: 650px;
              padding: 0 4px 0 8px;

              dl {
                border-top: 1px solid #eee;
                padding: 6px 0;
                overflow: hidden;
                zoom: 1;

                &.fore {
                  border-top: 0;
                }

                dt {
                  float: left;
                  width: 54px;
                  line-height: 22px;
                  text-align: right;
                  padding: 3px 6px 0 0;
                  font-weight: 700;
                }

                dd {
                  float: left;
                  width: 415px;
                  padding: 3px 0 0;
                  overflow: hidden;

                  em {
                    float: left;
                    height: 14px;
                    line-height: 14px;
                    padding: 0 8px;
                    margin-top: 5px;
                    border-left: 1px solid #ccc;
                  }
                }
              }
            }
          }
        }
        .cur {
          background-color: aqua;
        }
      }
    }
  }
}
</style>